Mailpiece creation systems such as mailpiece inserters are typically used by organizations such as banks, insurance companies, and utility companies to periodically produce a large volume of mailpieces, e.g., monthly billing or shareholders income/dividend statements. In many respects, mailpiece inserters are analogous to automated assembly equipment inasmuch as sheets, inserts and envelopes are conveyed along a feed path and assembled in or at various modules of the mailpiece inserter. That is, the various modules work cooperatively to process the sheets until a finished mailpiece is produced.
A mailpiece inserter includes a variety of apparatus/modules for conveying and processing sheet material along the feed path. Commonly mailpiece inserters include apparatus/modules for (i) feeding and singulating printed content material in a “feeder module”, (ii) accumulating the content material to form a multi-sheet collation in an “accumulator”, (iii) folding the content material to produce a variety of fold configurations such as a C-fold, Z-fold, bi-fold and gate fold, in a “folder”, (iv) feeding mailpiece inserts such as coupons, brochures, and pamphlets, in combination with the content material, in a “chassis module” (v) inserting the folded/unfolded and/or nested content material into an envelope in an “envelope inserter”, (vi) sealing the filled envelope in “sealing module” (vii) printing recipient/return addresses and/or postage indicia on the face of the mailpiece envelope at a “print station” and (viii) controlling the flow and speed of the content material at various locations along the feed path of the mailpiece inserter by a series of “buffer stations”. In addition to these commonly employed apparatus/modules, mailpiece inserter may also include other modules for (i) binding/to close the module to close and seal filled mailpiece envelopes and a (vi) a printing module for addressing and/or printing postage indicia.
With respect to the printing module, it is common to register a face surface of each mailpiece with a registration plate such that an array of print heads may print information such as destination and return addresses on the face of each mailpiece. More specifically, the registration plate includes an aperture for accepting a stepped array of print head nozzles. The thickness of the registration plate provides a threshold “stand-off” dimension from the face surface of each mailpiece to each of the print head nozzles such that ink droplets may be precisely deposited.
Furthermore, the array of print heads and registration plate are typically disposed over, and in opposed relation to, and underlying conveyance system such as one or more conveyor belts. Mailpieces are conveyed along the belt(s), move under the registration plate and passed by the print head nozzles as ink is deposited. To ensure that mailpieces slide smoothly beneath the registration plate, i.e., without jamming, the spacing between the underlying conveyance system, e.g., the conveyance belt (s), and the registration plate must be closely controlled. That is, with each mail run/print job performed by the print module, the necessary clearance gap must be established based upon the anticipated thickness of mailpieces being processed. As such, print head modules and underlying conveyance systems are typically limited to processing mailpieces having a constant, i.e., non-variable, thickness dimension. While such print head modules are capable of printing on thin and thick mailpieces, they are unable to print consecutive thin and thick mailpieces inasmuch as the clearance gap differs for each of the mailpieces.
Commonly, the mailpieces are conveyed along a feed path to the print heads by a vacuum conveyance/manifold system. The vacuum conveyance/manifold system develops a pressure differential across each of the mailpieces to urge each mailpiece into frictional engagement with one or more conveyor belts. A fluid communication path is created from the drive surface of the conveyor belts to a vacuum source by a combination of apertures, conduits and plenums. More specifically, rows of apertures are typically formed in the belts which communicate with a combination of elongate slots and circular apertures formed in the underlying support deck. Conventionally, a system of plenums are disposed beneath, and attached to an underside surface of, the support deck to draw air through the apertures of the belt and elongate slots/circular apertures of the support deck. The elongate slots are aligned with the apertures formed in the belts to ensure a flow of air to each of the apertures as the belts are driven along the feed path. To ensure that airflow is not restricted along the length of the elongate slots, i.e., due to deformation of the belt into an elongate slot, elongate slots are fabricated to maintain a threshold thickness dimension. That is, by maintaining a threshold minimum thickness, deformation of the belt may be obviated to prevent the belt from restricting or closing the flow through the slots and circular apertures of the support deck.
A need, therefore, exists for a print module and conveyance system which is capable of processing consecutive mailpieces which vary in thickness dimension while maintaining a robust vacuum conveyance/manifold system.